Act deliberately. Whatever you are doing, do it on purpose, consciously, intentionally; not automatically or mechanically. Be present within yourself as you act. Although this is a commonly taught meditation method, it has not been adequately explained what it means to act consciously.
In order to act consciously, you have to distinguish between what you are doing and how you are doing it. Once you verbalize what you are doing, watch how you do it. Ask yourself, how do you do this? And then, in answer, do it, as if you are showing someone else how to do it, where the emphasis is on how. Action is this how, whereas the what is just a thought about it, a mental concept of the action. Watch the how, making it deliberate and conscious.
In essence, the action and the thought about the action are two completely separate things, and while acting, the mind should become silent, so that the thought about the action does not interfere with the action.
Language is an aid to understanding this method. Describe to yourself what you are doing in “present progressive tense”. For example, “I am drinking water”. This complete sentence is the thought that describes what you are doing, a very static and flat description. Now be conscious of “how” you are drinking the water. This “how” has much more depth and activity, and can be either mindful or mindless. For example, the actual act of drinking water consists of individual movements of the hand as the cup is brought to the mouth, opening of the mouth, sipping the water, swallowing, and bringing the cup back down. Treat all of this as the encompassing, holistic act, “I am drinking water”; don’t make the mistake of slicing up the “how” into smaller “what” components in the mind, otherwise you will get stuck in a problem of infinite regress. Don’t verbalize further than the first description, but rather jump into the act, and be deliberate and mindful in how you do it. Again, keep in mind that this is a meditation method, and not meant to be any kind of philosophical or metaphysical argument.
If you are having trouble with the method, you can attempt the following experiment to make this distinction between what and how clearer: when you think about what you are going to do, put the thought in the form of a desired state. For example, if you want to wash your hands, the goal state is: “my hands are clean”. In this form of the thought, there should be no verb – so that you don’t get misled into believing that the thought is the action. It should just be a description of the state or condition that you desire to exist, without any sense of action in it. Once you have this form, then the actual act of washing your hands is how you reach that desired state of your hands being clean. When you proceed to wash your hands, be aware that this is how you are reaching your desired state, and consciously, on purpose, perform each movement that constitutes the action.
Pick small, tangible acts to practice this method. If the act is too complex, or too big, needing many decisions, evaluations, analysis, or steps, then the mind takes over and you lose your conscious connection to the act, and it becomes mindless.
The mature stage of this method is when you can act consciously without having to rely even on the mind’s description of what you are doing. In the beginning, the approach described above is a good way to bootstrap consciousness, but it is not the end goal. In the mature stage, the “how” becomes primary, and the “what” becomes secondary. This is an advanced stage which may take dedicated practice and perseverance to reach.